Different surgical procedures often make use of a method referred to as blunt dissection. Blunt dissection can be generally described as dissection accomplished by separating tissues along natural cleavage lines without cutting. Blunt dissection is executed using a number of different blunt surgical tools, as is understood by those of ordinary skill in the art. Blunt dissection is often performed in cardiovascular, colorectal, urology, gynecology, upper GI, and plastic surgery applications, among others.
In accordance with several methods of blunt dissection, a small incision is made in the patient. Specially designed blunt dissection tools having small profiles are inserted through the incision to the desired location in the body. Longer tools may be used to access locations substantially distal from the incision, while shorter tools can be used to access locations closer to the incision.
After the blunt dissection separates the desired tissues into separate areas, there is often a need to maintain the separation of those tissues. In fact, post surgical adhesions can occur following almost any type of surgery, resulting in serious postoperative complications. Adhesions may cause intestinal obstruction, bowel torsion, pain and infertility following general abdominal and pelvic surgery. Adhesions can also develop following orthopedic and cardiac surgery. Surgical adhesion disease is a complex inflammatory disease in which tissues that normally remain separated in the body grow into each other as a result of surgical trauma. Conventional surgical methods make use of anti-adhesion barriers, such as INTERCEED from Johnson & Johnson or SEPRAFILM from Genzyme Corporation.
INTERCEED is a fabric relatively easy to apply and handle. However, effectiveness may be diminished when bleeding has not been completely controlled. SEPRAFILM is widely used in general surgery. However, it is challenging for surgeons to apply and handle because of the film's tendency to easily break apart upon exposure to water due to their chemical make up and bio-dissolvable properties. The composition and structural properties of these bio-dissolvable products require that they be handled with dry hands or instruments, which can be difficult during most surgical intervention operations. Furthermore, many of these bio-dissolvable films are made intentionally thin to minimize tissue disruption and consequently end up being structurally weak (i.e., easily torn or folded during handling). In addition, SEPRAFILM is composed of two chemically modified biopolymers, sodium hyaluronate (HA) and carboxymethylcellulose (CMC), reacted with an activating agent 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) to form a water insoluble powder, hyaluronic acid-carboxymethylcellulose (HA-CMC). Although it is biodegradable, some of its breakdown products, such as smaller CMC units and ethyl-(3-dimethylaminopropyl)-urea (EDU), are not consumable by the patient's cell tissues. Hence, biodegradable substances, such as polymers, can cause inflammatory response due to either the parent substance or those substances formed during breakdown, and they may or may not be absorbed by tissues.
Another drawback of most barrier films is their non-elastic properties due to their sheet-like construction. In other words, the barrier films are not mechanically stretchable. Hence, it is difficult to use the barrier films to conform to three-dimensional surface of a tissue.